Celia has a bag of tennis balls and baseballs. there are 12 tennis balls and 5 baseballs. celia gave her sister 3 tennis balls. celia's sister already had 6 tennis balls. how many balls are left in celia's bag?
a. how many tennis balls does celia's sister have now?
b. how many tennis balls does celia have left in her bag?
c. how many balls did celia give to her sister altogether?
d. how many tennis balls and baseballs combined does celia have in her bag now?