I just need the code for interval_contains(self, x) that passes the test given. The parameter must be exactly followed how it was given.

only #2 represents an object at rest on a table.

in #1, there is no normal force due to the table; the object is accelerating downward.

in #3, the vertical forces are not balanced; the object is accelerating downward.

in #4, neither the vertical nor the horizontal forces are balanced. the object is accelerating upwards and to the right.

look at the engine block shown in the figure. the engine shown in this figure is a/an  

  a. four-cylinder, horizontally opposed engine.

  b. eight-cylinder, v-type engine.

  c. six-cylinder, v-type engine.

  d. four-cylinder, in-line engine