Read the following specifications for a function named fun$\_$conditions$()$:

ARGUMENTS:

: a numeric vector th no default value

: a numeric vector with default value equal to $1$

$,$ : a numeric vector with default value equal to the maximum of a and $b$

: an object with default value equal to

$fu{n}_c$onditions $(a,b,c,d)=\{\begin{array}{ccc}\frac{a+b}{c}& ifdis\text{e}\text{x}\text{a}\text{c}\text{t}\text{l}\text{y}\text{N}\text{U}\text{L}\text{L}& \\ a(b+c)& ifdis\text{e}\text{x}\text{a}\text{c}\text{t}\text{l}\text{y}\text{T}\text{R}\text{U}\text{E}& \\ \text{a}\text{m}\text{o}\text{d}& (b-c)ifdis\text{e}\text{x}\text{a}\text{c}\text{t}\text{l}\text{y}\text{F}\text{A}\text{L}\text{S}\text{E}& \\ a^b-c& in\text{a}\text{l}\text{l}\text{o}\text{t}\text{h}\text{e}\text{r}\text{c}\text{a}\text{s}\text{e}\text{s}& \end{array}$

Write a function named according to the above specifications. You may

not use while writing this function. You can assume that all inputs to the

function will be valid $($you do not have to perform any input validation$).$

Hint:

$d=1,$ and

all fall under the fourth case.