Which of the following proteins is insoluble in any solvent?

In a $p-n$ junction diode,the thickness of the depletion layer is $2 \times 10^{-6} ~m$ and the barrier potential is $0.3 ~V$. The intensity of the electric field at the junction is:

$A$ nucleus at rest undergoes $\alpha-$ decay according to the equation ${}_{92}^{226}X \to Y + \alpha$. At $t = 0$,the emitted $\alpha-$ particle enters a region of space where a uniform magnetic field $\vec{B} = B_0 \hat{i}$ and an electric field $\vec{E} = E_0 \hat{i}$ exist. The $\alpha-$ particle enters the region with velocity $\vec{v} = v_0 \hat{j}$ at $x = 0$. After a time $t = \sqrt{3} \times 10^7 \frac{m_{\alpha}}{q_{\alpha} E_0}$,the particle is found to have twice its initial speed. What is the initial speed $v_0$ of the $\alpha-$ particle?

An element $(X)$ forms compounds of the formula $XCl_3$,$X_2O_5$ and $Ca_3X_2$,but does not form $XCl_5$. Which of the following is the element $X$?

Identify the blank spaces $A, B, C$ and $D$ given in the following table and select the correct answer.

Types of Microbes	Scientific Name	Commercial Product
Bacterium	$A$	Clot buster enzyme
$B$	Aspergillus niger	Citric acid
Fungus	Trichoderma polysporum	$C$
Bacterium	$D$	Butyric acid

There is a horizontal film of soap solution. On it,a thread is placed in the form of a loop. The film is pierced inside the loop,and the thread becomes a circular loop of radius $R$. If the surface tension of the soap solution is $T$,then what will be the tension in the thread?