diff --git a/24.1.py b/24.1.py
new file mode 100644
index 0000000..7146806
--- /dev/null
+++ b/24.1.py
@@ -0,0 +1,49 @@
+from tkinter import *
+
+def func(x, eps):    
+    y = 1
+    y_0 = 1
+    n = 2
+    while abs(y_0) >= eps:
+        y_0 = (-1)**(n+1) * n * x**(n-1)
+        y += y_0
+        print(y)
+        n += 1
+
+    return y
+
+def calc():
+    x = float(x_entry.get())
+    eps = float(eps_entry.get())
+    assert abs(x) < 1, result_label.configure(text='Warning! |x| < 1')
+    assert eps > 0, result_label.configure(text='Warning! eps > 0')
+    ans = func(x, eps)
+    result_label.configure(text=f'Result: {ans}')
+    
+top = Tk()
+
+# X
+x_frame = Frame(top)
+x_frame.pack()
+Label(x_frame, font=('arial', 16), text='    X: ').pack(side=LEFT)
+x_entry = Entry(x_frame, font=('arial', 16))
+x_entry.pack()
+
+# Eps
+eps_frame = Frame(top)
+eps_frame.pack()
+Label(eps_frame, font=('arial', 16), text='Eps: ').pack(side=LEFT)
+eps_entry = Entry(eps_frame, font=('arial', 16))
+eps_entry.pack()
+
+# Result
+result_frame = Frame(top)
+result_frame.pack()
+result_label = Label(result_frame, font=('arial', 16), text='Result: ')
+result_label.pack(side=LEFT)
+
+# Button
+calc_button = Button(top, font=('arial', 16), text="Calculate", command=calc)
+calc_button.pack()
+
+top.mainloop()
\ No newline at end of file
diff --git a/24.2.py b/24.2.py
new file mode 100644
index 0000000..0eda179
--- /dev/null
+++ b/24.2.py
@@ -0,0 +1,30 @@
+from tkinter import *
+
+def is_palindrome(s):
+    if s == s[::-1]:
+        return 'YES'
+    else:
+        return 'NO'
+    
+def check():
+    s = string_entry.get()
+    ans = is_palindrome(s)
+    ans_label.configure(text=f'Is palindrome: {ans}')
+    
+top = Tk()
+
+# String
+string_frame = Frame(top)
+string_frame.pack()
+Label(string_frame, font=('arial', 16), text='Input string: ').pack(side=LEFT)
+string_entry = Entry(string_frame, font=('arial', 16))
+string_entry.pack()
+
+# Answer
+ans_label = Label(top, font=('arial', 16), text='Is palindrome: ')
+ans_label.pack()
+
+# Button
+Button(top, font=('arial', 16), text='Check string', command=check).pack()
+
+top.mainloop()
\ No newline at end of file
diff --git a/24.3.py b/24.3.py
new file mode 100644
index 0000000..fcfad7c
--- /dev/null
+++ b/24.3.py
@@ -0,0 +1,28 @@
+from tkinter import *
+
+def diff_words(s):
+    return set(s.split())
+
+def make_list():
+    string = diff_words(string_entry.get())
+    words_list.delete(0, END)
+    for word in string:
+        words_list.insert(END, word)
+    words_list.pack()
+
+top = Tk()
+
+# String
+string_frame = Frame(top)
+string_frame.pack()
+Label(string_frame, font=('arial', 16), text='Input string: ').pack(side=LEFT)
+string_entry = Entry(string_frame, font=('arial', 16))
+string_entry.pack()
+
+# Button
+Button(top, font=('arial', 16), text='Accept', command=make_list).pack()
+
+# Words list
+words_list = Listbox(top, font=('arial', 16))
+
+top.mainloop()
diff --git a/24.4.py b/24.4.py
new file mode 100644
index 0000000..d35fd11
--- /dev/null
+++ b/24.4.py
@@ -0,0 +1,41 @@
+from tkinter import *
+
+def sign_changes(nums=[], changes=0):
+    num = float(number_entry.get())
+    number_entry.delete(0, END)
+    if num == 0:
+        for i in range(len(nums)-1):
+            if (nums[i] > 0 and nums[i+1] < 0) or (nums[i] < 0 and nums[i+1] > 0):
+                changes += 1
+        ans = changes
+        while nums:
+            nums.pop()
+        changes = 0
+        return ans
+    else:
+        nums.append(num)
+
+def execution(ev=None):
+    ans = sign_changes()
+    if ans != None:
+        ans_label.configure(text=f'Number of sign changes: {ans}')
+        ans_label.pack()
+
+top = Tk()
+
+# Input number
+number_frame = Frame(top)
+number_frame.pack()
+number_label = Label(number_frame, font=('arial', 16), text='Input number: ').pack(side=LEFT)
+number_entry = Entry(number_frame, font=('arial', 16))
+number_entry.pack()
+
+# Button
+accept_button = Button(top, font=('arial', 16), text='Accept', command=execution)
+accept_button.pack()
+top.bind('<Return>', execution)
+
+# Answer
+ans_label = Label(top, font=('arial', 16))
+
+top.mainloop()
\ No newline at end of file