HELP ASAP PLS PLS PLS PLS

5× 1/2 = ? a) more than 5 because you are multiplying by a whole number b) 5/10 because you multiply the numerator and denominator by 5 c) less than 5 because you are multiplying by a number that is more than 1 d) less than 5 because you are multiplying by a number that is less than 1

The two square pyramids are similar. find the total volume of both pyramids if the ratio of their surface areas is 9/16

Solve this riddle: i am an odd number. i an less than 100. the some of my digit is 12. i am a multiple of 15. what number am i?