Write a program to read and total all numbers in a file

Prompt the user for a file name

Using exception handling:

Output a message, Could not open file $-$ exiting, if the file could not be opened$/$read and exit the program

Output a message, Invalid number: $,$ plus the bad line if the value on the line is not a floating point number

Print the grand total at the end of the program

nums$1.$txt contains:

$3$

$4\mathrm{.}5$

apple

$1$

banana

num$2.$txt contains:

$1\mathrm{.}2$

$3\mathrm{.}6$

$4\mathrm{.}2$

$-2\mathrm{.}1$

bad

$4$

Sample Run #$1($bold$,$ underlined text is what the user types$)$:

File? nums$1.$txt

Invalid number: apple

Invalid number: banana

Grand total: $8\mathrm{.}5$

Note: This is an introductore level class and this problem is meant to completed through a mixture of inputs$/$outputs$,$ and exceptions.