Help me solve this with the conservative approah$-$

The company uses Straight$-$Line Depreciation for its Plant and Equipment. Plant and Equipment costs are:

Building $710,000($range $20$ to $40$ years$)$

Furniture $130,000($range $150$ to $20$ years$)$

Computers $20,000($range $1$ to $7$ years$)$

TOTAL $860,000$