Which algae is rich in protein?

Two identical piano wires have a fundamental frequency of $600 \text{ Hz}$ when kept under the same tension. What fractional increase in the tension of one wire will lead to the occurrence of $6 \text{ beats per second}$ when both wires vibrate simultaneously?

The maximum value of $xy$ subject to $x+y=7$ is

The normal at a point on the parabola $y^2=4x$ passes through $(5,0)$. If two more normals to this parabola also pass through $(5,0)$,then the centroid of the triangle formed by the feet of these three normals is

Given below are two statements:
Statement $I$: $[CoBr_{4}]^{2-}$ ion will absorb light of lower energy than $[CoCl_{4}]^{2-}$ ion.
Statement $II$: In $[CoI_{4}]^{2-}$ ion,the energy separation between the two sets of $d$-orbitals is more than $[CoCl_{4}]^{2-}$ ion.
In the light of the above statements,choose the correct answer from the options given below:

Which one of the following statements in regard to the excretion by the human kidneys is correct?