Backbone of DNA strand is built up ofa. nitrogen base, phosphate and deoxyribose sugar b. alternate nitrogen base and phosphate c. alternate nitrogen base and deoxyribose sugar d. alternate phosphate and deoxyribose sugar

Certainly! Here are some examples of step-by-step solutions using LaTeX: Example 1: Solving an equation Given the equation $3x+5=14$, solve for $x$. $\begin{array}{rl}3x+5& =14\\ 3x& =9\\ x& =3\end{array}$ Therefore, the solution is $x=3$. Example 2: Proving an identity Prove the identity ${\sin }^{2}x+{\cos }^{2}x=1$. $\begin{array}{rl}{\sin }^{2}x+{\cos }^{2}x& =1\\ \frac{{\sin }^{2}x}{{\cos }^{2}x}+1& =\frac{{\cos }^{2}x}{{\cos }^{2}x}\\ \frac{{\sin }^{2}x+{\cos }^{2}x}{{\cos }^{2}x}& =1\\ \frac{1}{{\cos }^{2}x}& =1\\ {\cos }^{2}x& =1\\ \cos x& =\pm 1\end{array}$ Since $\cos x$ can only take on the values of $1$ or $-1$, the identity is proven. Example 3: Finding the derivative of a function Find the derivative of $f(x)=2x^3-4x+1$. $\begin{array}{rl}{f}^{\prime }(x)& =\frac{d}{dx}(2x^3-4x+1)\\ & =6x^2-4\end{array}$ Therefore, the derivative of $f(x)$ is $f^{\prime }(x)=6x^2-4$.