A diver begins at sea level and descends into a cave at 3.1/2 feet per second. He descends for 30 seconds. Then he swims back up to the surface in 21 seconds. What was his speed going back up to the surface?

Find the x-intercept and y-intercept of the line. 3x + 5y = −15

Look at triangle wxy what is the length (in centimeters) of the side wy of the triangle?

Many newspapers carry a certain puzzle in which the reader must unscramble letters to form words. how many ways can the letters of emdangl be arranged? identify the correct unscrambling, then determine the probability of getting that result by randomly selecting one arrangement of the given letters.