How much energy, in joules, is released by an earthquake of magnitude 4?

Afarm that has 4 x 10^2 acres has 1.2 x 10^5 cattle. what is the average number of cattle per acre? write the answer in scientific notation. answere asap

The amount spent on food and drink by 20 customers is shown below what is the modal amount spent ?

Laura read 1/8 of a comic book in 2 days. she reads the same number of pages every day. what part of the book does she read in a week