Suppose 2kg of a radioactive substance decays to 250g in 75years .what is the half-life of the substance ?

Out of $20$ creepy-crawly creatures in a room, $80\%$ are flies and $20\%$ are spiders. if $s\%$ of the total legs belong to spiders, what is $s$?

Find the area between y=e^x and y=e^2x over [0,1]

The price of a lawn mower is x dollars. the store is having a 75% end of summer clearance sale. which expression can be used to find the clearance price of the mower? a) .25x b) .75x c) x - .25(75) d) x + .25(75)