Which expression cannot be used to calculate the sale price of a fish tank that was originally at priced d dollars and is on sale for 25%?

Cody started biking to the park traveling 15 mph, after some time the bike got a flat so cody walked the rest of the way, traveling 4 mph. if the total trip to the park took 6 hours and it was 46 miles away, how long did cody travel at each speed? solve using rate times time= distance

Tan198=asin164=? how to solve this? ?

How is this equation completed? i cannot find any examples in the book.