If l and k are lines in the xy-plane, is the product of the slopes of l and k equal to -1 ?

(1) Line l passes through the origin and the point (1, 2).
(2) Line k has x-intercept 4 and y-intercept 2.

The positive integer k has exactly two positive prime factors, 3 and 7. If k has a total of 6 positive factors, including 1 and k, what is the value of k ?

(1) 3² is a factor of k.

(2) 7² is not a factor of k.

The points A, B, C, and D are on a number line, not necessarily in that order. If the distance between A and B is 18 and the distance between C and D is 8, what is the distance between B and D ?

(1) The distance between C and A is the same as the distance between C and B.
(2) A is to the left of D on the number line.

On the number line, if the number k is to the left of the number t, is the product kt to the right of t ?

(1) t < 0
(2) k < 1

S is a finite set of numbers. Does S contain more negative numbers than positive numbers?

(1) The product of all the numbers in S is -1,200.
(2) There are 6 numbers in S .

The sequence a₁, a₂, a₃, . . . , a_n of n integers is such that a_k = k if k is odd and a_k = -a_{k - 1} if k is even. Is the sum of the terms in the sequence positive?

(1) n is odd.
(2) a_n is positive.

A certain company divides its total advertising budget into television, radio, newspaper, and magazine budgets in the ratio of 8 : 7 : 3 : 2, respectively. How many dollars are in the radio budget?

(1) The television budget is $18,750 more than the newspaper budget.
(2) The magazine budget is $7,500.

If integer p is greater than 1, is p a prime number?

(1) p is odd.
(2) The only positive factors of p are 1 and p.

During a 40-mile trip, Marla traveled at an average speed of x miles per hour for the first y miles of the trip and at an average speed of 1.25x miles per hour for the last 40 - y miles of the trip. The time that Marla took to travel the 40 miles was what percent of the time it would have taken her if she had traveled at an average speed of x miles per hour for the entire trip?

(1) x = 48
(2) y = 20

How many of the students in a certain class are taking both a history and a science course?

(1) Of all the students in the class, 50 are taking a history course.
(2) Of all the students in the class, 70 are taking a science course.