answer:To solve the given expression step-by-step, we start with the original expression and simplify it using known values and properties:[2sin 60^{circ}+(-frac{1}{2})^{-2}-|2-sqrt{3}|-sqrt{12}]First, we know that sin 60^{circ} = frac{sqrt{3}}{2}, (-frac{1}{2})^{-2} = 4, and sqrt{12} = 2sqrt{3}. Also, |2-sqrt{3}| simplifies as follows: since 2 > sqrt{3}, |2-sqrt{3}| = 2-sqrt{3}. Putting these values into the expression, we get:[= 2times frac{sqrt{3}}{2} + 4 - (2 - sqrt{3}) - 2sqrt{3}]Simplifying further:[= sqrt{3} + 4 - 2 + sqrt{3} - 2sqrt{3}]Combining like terms:[= sqrt{3} + sqrt{3} - 2sqrt{3} + 4 - 2][= 2sqrt{3} - 2sqrt{3} + 2][= 2]Therefore, the final answer is boxed{2}.

answer:Let the angle of inclination of line l_1 be alpha, then the angle of inclination of line l_2 is 2alpha,Since line l_1: 2x-y+1=0, we have tanalpha=2,Therefore, tan2alpha= frac {2tanalpha}{1-tan^{2}alpha} = -frac {4}{3}, which means the slope of line l_2 is -frac {4}{3},Thus, the equation of line l_2 is y-1=-frac {4}{3}(x-1),Converting it into the standard form, we get 4x+3y-7=0.Hence, the correct choice is: boxed{text{A}}The problem involves the concept of the angle of inclination and the standard form equation of a line, including the formula for the tangent of a double angle, which is a basic question.

answer:In the maximum set of fences, there is a fence that limits exactly two houses. By combining these two houses into one, we reduce the number of houses by 1 and the number of fences by 2. In this process, both conditions of the problem are maintained. Continue this process. After 99 steps, one house and one fence will remain. And we have removed 198 fences. Therefore, there were 199 in total.## Answer199 fences.

answer:The sum of the subtrahend and the difference is equal to the minuend.## Otвет1008.

answer:From the graph and properties of the logarithmic function y=log_{0.7}x, we know that log_{0.7}6 1. Therefore, log_{0.7}6 < 0.7^6 < 6^{0.7}. Hence, the correct option is boxed{text{D}}.

answer:Solution to Exercise 14: Let's note that d divides n and d^{3}, so d divides a^{3}. Since a is prime, we get that d=1, a, a^{2} or a^{3}.If d=1, the equation becomes n=a^{3}+1. Since a divides n, a divides n-a^{3}=1 so a=1, which is a contradiction. Otherwise, d=a, a^{2} or a^{3}, and thus d has the same parity as a, so d^{3} has the same parity as a^{3}. In particular, n=a^{3}+d^{3} is the sum of two numbers of the same parity, so it is even. Since n is divisible by 2, we must have a=2. Thus d=2,4,8.Let's check the potential values of n:triangleright If a=2 and d=8, we get n=8+512=520=8 times 65 so d divides n well, the smallest divisor of n different from 1 is 2: n=520 is a solution.triangleright If a=2 and d=4, n=8+64=72=4 times 18 so d divides n well, the smallest divisor of n different from 1 is 2: n=72 is a solution.triangleright If a=2 and d=2, n=8+8=16=2 times 8 so d divides n well, the smallest divisor of n different from 1 is 2: n=16 is a solution.The solutions are therefore n=16, n=72, n=520.