Answer:
Step-by-step explanation:
For a number to be divisible by 4 you just need to worry about the 10s and 1s place. You also want to know that the 1s cylce every 20, or in other words:
4 8 12 16 20
24 28 32 36 40 and so on. So the only numbers that x can be there are 1, 3, 5, 7, 9. Does that make sense? and can you manage the rest?
Step-by-step explanation:
Follow PEMDAS

P: Parentheses
E : Exponents
M: Multiplication
D: Division
A: Addition
S: Subtraction

Question 2

No, you would only need to multiply 16 by 5 once
Answer:
Fish A is 4 inches.
Fish B is 5 inches.
Step-by-step explanation:
22=3a+2b
and
32=3a+4b
So,
a=4 and b=5