Solution:

20741616380

Explanation:
5 * 5 - 5 =>20
20 * 20 - 20 => 380
380 * 380 -380 =>144020
144020 * 144020 - 144020 => 20741616380

Solution:

As we have been informed that the prices are a full dollar increment, this eases out the situation.

If we look at the price of pineapple and capsicum, we can easily make out that both of them are priced $1.
This is because the price has to be at least $1 and since both of them costs $2 together, they must cost $1 separately.

Solving the rest of the question is child’s play. You have to use simple mathematics.

For an instance:
Jalapeno + Pineapple = $5
Now, we know that pineapple costs $1. Thus,
Jalapeno + $1 = $5
Jalapeno = $4

You can find out the price for each one of the toppings in a similar fashion.
Capsicum $1
Pineapple $1
Mushrooms $3
Corn $2
Jalapeno $4
Red Pepper $2
Black Pepper $3
Olives $4

Solution:

-3 -1 1

Explanation:
-3 * 1 * -1 = 3(prime)
-1 - (-3) = 1 -(-1) = 2

Solution:

I am word "Introvert"

Solution:

SC

12 zodiac signs are : Aries Taurus Gemini Cancer Leo Virgo Libra Scorpio Sagittarius Capricorn Aquarius Pisces

Solution:

Uncle Scrooge tells him he took the loan to keep his expensive car safe and he also saves money on security and parking rent.

Solution:

We just added four matchsticks as shown in below picture.

Solution:

Both will rotate at Same speed.

Explanation:
Gears of the same size will always rotate at constant speeds despite any smaller or larger gears in between them.

Solution:

When he is rowing the boat in the river, the boat is floating with watermelons in it and, therefore, all the watermelons have already displaced the water equal to their volume. Hence, there won't be any change in the water level, whether the farmer eats it or throws them away.

Solution:

It's Ice.