8) 18 is 9x2, [tex] \sqrt{18} = \sqrt{9*2} = \sqrt{9} \sqrt{2} = 3 \sqrt{2} [/tex] = 3 * about 1.4 = something above 4 (answer 3)
9) 3800 miles / 200 miles a year = 19 years.... 1957+19 years = 1976 (answer 4)
10) individuals + defence = 25% + 42 % = 67%, this means that 100%-67% = 33% left (answer 3)
11) not enough info given. they should give you height of fence - answer 5