Can somebody help me with my psychology

Clara solved the equation 7/3x = −2/3 as shown → 7/3x( 3/7 ) = −2/3 ( 3/7 ) x = −14 what is clara’s error?

The following frequency table relates the weekly sales of bicycles at a given store over a 42-week period. value01234567frequency367108521(a) in how many weeks were at least 2 bikes sold? (b) in how many weeks were at least 5 bikes sold? (c) in how many weeks were an even number of bikes sold?

Which is f(5) for the function –2x2 + 2x - 3?