Please figure this out I’ll give brainlest and 5 stars but if it’s incorrect you won’t get it good luck <3

For one history test, keith had to answer 40 questions. of these 40 questions, keith answered 28 of them correctly. what percent did keith get on his history test? round your answer to the nearest tenth if necessary

Which data set has a greater spread? why? set a: {38, 12, 23, 48, 55, 16, 18} set b: {44, 13, 24, 12, 56} has a greater spread because .

What is the number 321,000,000 in scientific notation? also what is the number? ?