1. P=__KQ__^{3}

√R

35 =__ K x 8 x 8 x 8__

√144

35=^{512k}/_{12}

K= ^{105}/_{128}

P = __ 105Q__^{3}

128√R

P= __ 105 x 20__^{3}

128 x √225

= __105 x 8000m__

128 x 15

=437.5

2. Original value of P =__KQ__^{3}

√R

new value = __K x (0.76Q)__^{3}

√1.4R

=__ 0.438976KQ__^{3 }

1.1832√R

= __0.3710 KQ__^{3}

√R

change = (0.3710 -1) __KQ__^{3}

√R

__0.6290KQ__^{3}

√R

%change = -0.6290 x 100

-62.90%

P has decreased by 62.90%