What is velocity ratio of a lever is 3 and efficiency of a pulley is 60%?

Which shows the correct solution of the equation 1/2a+2/3b=50, when b=30?

Will give a: 122 b: 90 c: 48 d: 180

Ineed asap. 35 points. in order for two polygons to be similar, two conditions must be met. first, all pairs of corresponding sides must be in proportion. second, all corresponding angles must be congruent. prove that angle congruence is not enough, by itself, to establish that two polygons are similar. do this by describing or drawing two polygons that are not similar but whose corresponding angles are all congruent.