Answer:
The correct answer is option D.
Explanation:
From the given options the reaction which is not a double replacement reaction is:

This because the above reaction is an example of single replacement reaction.

Whereas;
Double replacement reaction is a type of chemical reaction in which exchange of ions among the reactants take place.

Answer:
Power, P = 722.96 watts
Explanation:
It is given that,
Voltage, V = 120 V
Length of nichrome wire, l = 8.9 m
Diameter of wire, d = 0.86 mm
Radius of wire, r = 0.43 mm = 0.00043 m
Resistivity of wire, 
We need to find the power drawn by this heater. Power is given by :

And, 


P = 722.96 watts
So, the power drawn by this heater element is 722.96 watts. Hence, this is the required solution.
Answer:
GE = ME -
, which agrees with option C in your list.
Explanation:
The definition of Mechanical Energy (ME) of a system is the addition of the gravitational potential energy (GE) plus the kinetic energy (KE) of the system:
ME = GE + KE
Given that the KE is:
,
solving for GE in the formula above gives:
GE = ME - KE = ME -
, which agrees with option C
Explanation:
a) 7.5= 111.1×2°= 0.1111×2^3
which can also be written as
(1/2+1/4+1/8+1/16)×8
sign of mantissa:=0
Mantissa(9 bits): 111100000
sign of exponent: 0
Exponent(5 bits): 0011
the final for this is:011110000000011
b) -20.25= -10100.01×2^0= -0.1010001×2^5
sign of mantissa: 1
Mantissa(9 bits): 101000100
sign of exponent: 0
Exponent(5 bits): 00101
the final for this is:1101000100000101
c)-1/64= -.000001×2^0= -0.1×2^{-5}
sign of mantissa: 1
Mantissa(9 bits): 100000000
sign of exponent: 0
Exponent(5 bits): 00101
the final for this is:1100000000100101