Can someone me with this math problem? ? number 13

You have two cards with a sum of -12 in both hands. a. what two cards could you have? b. you add two more cards to your hand, but the total sum if the cards remains the same, (-12).

Acar travels at an average speed of 52 miles per hour. how long does it take to travel 299 miles

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%