Riverbed Inc. incurred the following costs during the year ended December $31,2021$:

Laboratory research aimed at discovery of new knowledge

Costs of testing prototype and design modifications

$$4296000$

Quality control during commercial production, including routine

$725500$

testing of products

$475000$

On December $31,2021,$ purchase of research facilities having an

estimated useful life of $20$ years with alternative future use in other

research & development projects

The total amount to be classified and expensed as research and development in $2021$ is

$$5496500.$

$$4771000.$

$$12376500.$

$$5021500.$