Which set of numbers could be the lengths of the sides of a triangle?

a. 2, 5, 4
b. 3, 5, 9
c. 4, 9, 3
d. 17, 15, 2

4. a spring scale is constructed so that each 0.10-n increment is separated by 0.50 cm. what spring constant is necessary for the scale to be accurate? -1.0n/cm -0.10n/cm -9.8 n/cm -0.20n/cm

Dylan and dusty plan to take weekly surfing lessons together. if the 2-hour lessons are $20 per person and they plan to spend $100 each on new surfboards, what is the maximum number of lessons the two can take if the total amount spent for lessons and surfboards is at most $480?

Which expression is equivalent to 8(k + m) − 15(2k + 5m)?