A hiker travels south along a straight path for 1.8 hours with an average velocity of 0.59km/hr, then travels south for 2.9 hours with an average velocity of 0.85 km/hr. what is the hiker’s displacement?

Answer(b) 60 miles per hour;

How is it possible that phylogenies based on sequences from nuclear genomes and organellar genomes (i.e., chloroplasts and mitochondria) from the same group of species yield phylogenetic trees with different branching orders?   answer :   the genome of the endosymbiont is more closely related to members of the group in which it originally evolved, while the nuclear genome of the engulfing organism has its own evolutionary trajectory.