It's hard for me but is it hard for you lets see your answers?

Determine the difference: 3.2 × 1010 – 1.1 × 1010. write your answer in scientific notation.

Abag contains 4 red, 7 blue and 5 yellow marbles. event a is defined as drawing a yellow marble on the first draw and event b is defined as drawing a blue marble on the second draw. if two marbles are drawn from the bag, one after the other and not replaced, what is p(b|a) expressed in simplest form? a. 7/16 b. 7/15 c. 14/16 d. 14/15

1: 4 if the wew 35 surfboards at the beach how many were short boards?