Simplify:
a) 3a²b + 4a²b - a²b =
b) 3a²b + 4ab² + 2a²b =
c) 3a²b + 4a² + a²b + 6a² =
d) 3a²b +4a² + a²b + 6b² =

If a boat travels 3 miles in 1.5 hours how far will it travel in 1 hour

He weights of 2-pound bags of best dog food are approximately normally distributed with a given mean  and standard deviation  according to the empirical rule, what percentage of the bags will have weights within 3 standard deviations of the mean? 47.5%68%95%99.7%

Someone answer asap for ! the following statements are true about the coins calvin and sasha have collected. * calvin and sasha has the same amount of money. * calvin has only quarters. * sasha has dimes, nickels, and pennies * calvin has the same number of quarters as sasha has dimes. * sasha has $1.95 in coins that are not dimes. exactly how many quarters does calvin have?