Our product and our sum always give the same answer. Who are we?

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?

Replace The Question Mark Below With the Correct Number.

2 {38} 3
4 {1524} 5
6 {3548} 7
8 {????} 9

Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

Solve the below puzzle by replacing the question mark with the correct number.

3 6 12

4 8 16

5 10 ?

Dwayne Johnson was running away with the loot from a heist in his car along with Vin Diesel. One tire was punctured and he dropped down to replace it. While changing the wheel, he dropped the four nuts that were holding the wheel and they fell into a drain. Vin Diesel gave him an idea using which they were able to drive till the rendezvous point.

What was the idea ?

What word is pronounced the same if you take away four of its five letters?

Spot what is wrong here in below Picture?

Why is the Hole below a Lock?

Which city is three-fifths chick two third cat and 50% goat?