Let {2,3,4} and {8,9,10}. Define a relation H from A to B such that (x, y)∈H if and only if y−x2 is an integer. Find the number of elements of H.

Initially 100 milligrams of a radioactive substance was present. after 6 hours the mass had decreased by 4%. if the rate of decay is proportional to the amount of the substance present at time t, find the amount remaining after 24 hours. (round your answer to one decimal place.)

Find the slope of the line that contains the following points. r(-2, 4), s(6, -2)

Sam opened a money-market account that pays 3% simple interest. he started the account with $7,000 and made no further deposits. when he closed the account, he had earned $420 in interest. how long did he keep his account open?