13 saci cu cartofi și 18 saci cu ardei gras cântăresc 300 kg. 18 saci cu cartofi și 18 saci cu ardei gras cântăresc 360 kg. Cât cântărește un sac cu cartofi? Dar unul cu ard zi gras?
7 va rog am nevoieee​

Atriangle has a side lengths of 18cm, 80 cm and 81cm. classify it as acute obtuse or right?

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)

Which statement is true about a number and its additive inverse? a. their product is always one. b. their sum is always one. c. they are always reciprocals of each other. d. their sum is always zero.