`(-2)\xx\ (-3)\xx\ 6\ xx\ (-1)` is equal to
(a)36
(b) `-36`
(c) 6
(d) `-6`

(-12)\xx\ (-9)-6\ xx\ (-8) is equal to: (a) 156 (b) 60 (c) -156\ (d) -60

(-6)xx(-5)xx0 is equal to

6^5 x 6^5 is equal to: (a) 36^5 (b) 6^25 (c) 6^5 (d) 12^5

5.2 - 3.6 is equal to

(-3)xx(-6)xx(-2)xx(-1)

(-3)xx(-6)xx(-2)xx(-1)

(-1)xx(-5)xx(-4)xx(-6)

(-1)xx(-5)xx(-4)xx(-6)

Find each of the following products: (a) 3 xx (-1) (b) (-1) xx 225 (c) (-21) xx (-30) (d) (-316) xx (-1) (e) (-15 xx 0 xx (-18) (f) (-12) xx (-11) xx (10) (g) 9 xx (-3) xx (-6) (h) (-18) xx (-5) xx (-4) (i) (-1) xx (-2) xx (-3) xx 4 (j) (-3) xx (-6) xx (-2) xx (-1)

The values of k for which the quadratic equation 16 x^2+4k x+9=0 has real and equal roots are (a) 6,\ -1/6 (b) 36 ,\ -36 (c) 6,\ -6 (d) 3/4,\ -3/4