Questions

Given that, a woman has seven children. Half of them are boys. 

Half of 7 is 3.5 which is not possible. And it is possible in only one way that all the children must be boys. Then half of them are boys.

Lithium is the lightest of all the metals due to its low atomic number among metals. It is the lightest solid element.

Properties ::

* It is a soft silvery-white alkali metal.

* Lithium is highly reactive and flammable and is stored in mineral oil.

Most operating systems store files on a hard disk.

In this chemical reaction chlorine change oxidation number from 0 to -1 (reduction) and bromine change oxidation number from -1 to 0 (oxidation).

Chlorine is stronger oxidation reagent than bromine.

In VIIA or group 17 (halogen elements) there are six elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At) and tennessin(Ts).

They have high electronegativity because they have seven valence electrons in their outermost energy level, so they can gain an electron to have the octet rule.  

Going down in the group, element are weaker oxidazing reagent and less reactive.

A fixture is defined as a device which holds and locates a workpiece and guides and controls one or more cutting tools.

Let the required weight be x kg.

Less weight, Less cost (Direct Proportion)

 250 : 200 :: 60 : x   =>    250 x x = (200 x 60)

=>

=> x = 48.