Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_77 (elevation__ft_ INTEGER, isolation VARCHAR, range VARCHAR, peak_name VARCHAR)
### Question:
WHAT IS THE ELEVATION OF THE UNAKA MOUNTAINS, IN ROAN HIGH BLUFF PEAK, AND ISOLATION LARGER THAN 1.54?
### Answer:
SELECT AVG(elevation__ft_) FROM table_name_77 WHERE range = "unaka mountains" AND peak_name = "roan high bluff" AND isolation > 1.54