Answer:
Explanation:
Using the pythagoras theorem, the displacement is expressed as;
d² = x²+y²
y = 36m (north)
x = 20m east
Substitute;
d² = 36²+20²
d² = 1296+400
d² = 1696
d = √1696
d = 41.18m
For the direction;
theta = tan^-1(y/x)
theta = tan^-1(36/20)
theta = tan^-1(1.8)
theta = 60.95°
Hence the magnitude is 41.18m and the direction is 60.95°
Answer:

Explanation:
As we know that melting point of silver is
T = 961.8 degree C
Latent heat of fusion of silver is given as
L = 111 kJ/kg
specific heat capacity of silver is given as

now we will have



now from above equation



Answer:The frequency of the echo is slightly decreased
Explanation:
Given
speed of boat 
cliff is
away
when boat is still , suppose t is the time taken by the echo to reach observer on the boat
But as soon as boat starts moving the distance between cliff and boat decreasing and time for echo to reach observer also decreases
and we know 
therefore frequency of the echo slightly decreased.
In the writing of ionic chemical formulas the value of each ion's charge is crossed over in the crossover rule.
Rules for naming Ionic compounds
- Frist Rule
The cation (element with a negative charge) is written first in the name then the anion(element with a positive charge) is written second in the name.
- Second rule
When the formula unit contains two or more of the same polyatomic ion, that ion is written in parentheses with the subscript written outside the parentheses.
Example: Sodium carbonate is written as Na₂CO₃ not Na₂(CO)₃
- Third rule
If the cation is a metal ion with a fixed charge then the name of the cation will remain the same as the (neutral) element from which it is derived (Example: Na+ will be sodium).
If the cation is a metal ion with a variable charge, the charge on the cation is indicated using a Roman numeral, in parentheses, immediately following the name of the cation (example: Fe³⁺ = iron(III)).
- Fourth rule
If the anion is a monatomic ion, the anion is named by adding the suffix <em>-ide</em> to the root of the element name (example: F = Fluoride).
The oxidation state of each ion is also important, thus in the crossover rule, the value of each ion's charge is crossed over.
Learn more about chemical formulas here:
<u>brainly.com/question/11995171</u>
#SPJ4