First expression:
For the first expression, remember that parenthesis have priority over other operations. Inside the parenthesis we have the sum of three terms (once you read it as 5 + (-3) + 2. Since the sum is commutative and associative, you can perform this operations in any way you like.
The expression in the parenthesis evaluates to 4, so we're left with 16(4), which means we have to mulply 16 by 4, and the answer is 64
Second expression:
Here, you must use the fact that multiplications/divisions have higher priority than sums/subtractions, so we must perform that operation first. The multiplication is three times four, so the answer is 12. The expression becomes, as before, the sum of three terms:
