help please

for the program please unse b mobaexterm editor

1. # include 2. int main (); etc

please solve only for 4

4. Considering the string statements below and assuming s1, s2 and s3 have been defined as strings (i.e., char [20]), answer questions a to c: (i) sl=strlen(s2); (ii) s3=s2 s1; (iii) printf("%s", s2); (iv) s2 [4] =s 3[5]; (v) s2="AmIcorrect?"; un uus a. Which statements are not syntactically correct? Why? 5 b. Which statement(s) returns the size of a string? 5 c. Which statement(s) copy a part of a string to another? 5 5. Write a program that takes as input 20 numbers and calculates their sum and their average value. The numbers should be given all together and the program should not ask all the 20 numbers one-by-one. This can be done from either the command line or using scanf. 6. You are given the code below. It's a game where the user has to guess a sequence of